Rubber mailbox



FIG. 1 is an enlarged top, front and left-side perspective view of a rubber mailbox showing our new design;

FIG. 2 is a front elevational view;

FIG. 3 is a rear elevational view;

FIG. 4 is a left side elevational view;

FIG. 5 is a right side elevational view; and,

FIG. 6 is a top plan view thereof. 

We claim the ornamental design for a rubber mailbox, as shown and described. 